Friday, August 24, 2012

WHAT IF IT RAINS

85. WHAT IF IT RAINS – PASTURES




Today let’s play a little game of ‘what if’. As in ‘what if it rains’? What if your pastures and hay meadows green up and grow. Should you graze? Stay tuned.







What if it rains? What if it rains enough for your pasture to green up and grow enough to graze? Will you succumb to the temptation?



As tempting as it may be to give your animals some nice green grass, resist that temptation. If you do graze, it might do more harm to your grass than if it did not rain at all.



How can that be? To understand this risk, we need to review what happens when a dormant plant starts to grow. When a dormant plant starts to green up and grow, like in the spring following winter or after a rain during a drought, the plant mobilizes nutrients from its root system to energize the initial growth. This process actually weakens the root system and the plant temporarily. As the plant grows and produces more leaves, those leaves eventually harvest enough sunlight energy to replace the nutrients used during the green up process.



However, if some of the leaves are removed by grazing before they replace the nutrients used during green up, the plant will try to mobilize even more root nutrients to restart the process. At this time of year, though, the plant actually needs to increase root nutrients for winter survival. If grazing prevents that from happening, plants will go into winter in a very weakened condition. Some may die. And those that survive to next spring will grow very slowly until they have recovered from the multiple stresses of drought and untimely grazing.



So do yourself and your pastures a favor. Decide right now that no matter what happens this fall, you will not graze green growth again until next year. Pasture survival may depend on it.











86. WHAT IF IT RAINS – ALFALFA



Many dryland alfalfa fields have been sitting dormant for many weeks. If it rains heavily, how should you manage any cuttings if that alfalfa begins to regrow. Stick around.







If it rains very much in the next few weeks, dormant alfalfa is going to start to regrow. If that happens, what should you do?



To be honest, I really don’t know. We are kind of in uncharted territory with newer alfalfa varieties and this severity of drought.



It might depend on when that rain occurs and if it becomes enough to support regular growth rates. Since we are approaching the usual winterizing season for alfalfa, I think alfalfa that has been virtually dormant the past few weeks should be allowed to grow without any harvest at least until mid-October.



About the only exception to that recommendation might be to consider a salvage harvest or a stimulation harvest.



A salvage harvest would be a situation where your alfalfa has gone fully dormant due to drought, there is enough standing growth to harvest economically, and that standing growth is starting to drop leaves. It doesn’t matter if it rains or not. Harvest shouldn’t hurt that stand and harvest will give you some needed feed.



A stimulation harvest would involve cutting off any standing crop immediately before or as soon as possible after a heavy rain to encourage new shoots. Regrowth then may develop a little faster without the influence of a standing crop. It isn’t necessary to cut off the standing crop to get new growth but it might help.



It’s been a tough year for alfalfa. Without rain, some of it may not survive the winter. But with rain we must be careful to allow the plants adequate time to winterize. Maybe then, next year will be better.











87. BALING CORN OR MILO STALKS FOR WINTER FEED



Your corn is getting combined. Now you are wondering if you should bale some of the stalks. Is it worth it? Stick around.







What are corn stalk bales worth? Let’s first look at it from the cost stand point.. Nutrients removed by stalk bales may need to be replaced with extra fertilizer. Using this year’s prices, stalks may contain over fifteen dollars worth of nitrogen, phosphate, sulfur, and lime per ton.



Corn stalk removal also can reduce soil organic matter, increase erosion risk, and increase soil water evaporation. Nebraska research shows that the decline in dryland corn yield or the increase in irrigation needs costs about ten to twenty dollars for each ton of residue removed.



Labor and equipment costs average over thirty dollars per ton, and baling stalks tends to cause more wear and tear on equipment than other baling operations. Totaled together, these costs amount to at least sixty dollars per ton of corn stalks removed.



So, what are corn stalks worth as a feed? Some folks suggest the dollar feeding value is midway between that of straw and prairie hay. But feed value of stalks varies greatly, and cattle tend to waste more of it. If you bale the entire field you may only have three to four percent protein and less than fifty percent TDN. Harvest just the tailings in the two or three rows behind the combine and TDN increases to the lower fifties and protein to about five percent. But test to make sure. And don’t forget to test for nitrates this year.



Are baled corn stalks worthwhile? Maybe so this year considering how expensive other alternatives might be. But first make sure they fit your feeding program without damaging next year’s crop production.















* * * * * * * * * * * * * * * * * * * * * * * * * * * *



Bruce Anderson



Extension Forage Specialist



Department of Agronomy & Horticulture



University of Nebraska



Lincoln, NE 68583-0910



Voice: 402-472-6237



Fax: 402-472-7904



Email: banderson1@unl.edu



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